The man in the sepia photo, known as White Swan of the Crow nation, stands with a striped shirt and elaborate feathered headdress. With a hint of a smile on his face, his left hand palms a holstered pistol. Another image shows a woman of the Arapahoe nation, in a blouse richly decorated with neat rows of large, sewn-on beads. Yet another depicts Black Wezel of the Blackfoot nation, seated and sporting a Western-style suit and shirt, a round earring dangling off his left ear. They were all attendees of…